If your engine is currently working OK, you can run it with DOD disabled. The failure happens when DOD tries to reactivate the lifters and one stays locked in the collapsed state. Just run it like this and see if your oil consumption improves. The smoke on startup could be the valve stem seals.
At this age and mileage, it could have already been repaired in the past by the dealer, which usually used improved parts.
Yeah, never trust new tech, like this DOD when it first came out. It now seems to be good in newer vehicles having been beta tested by owners. However, I would steer clear on the new DFM (Dynamic Fuel Management) which will be in the new 4 cyl, turbo which has 24 modes rather than the 2 modes of the current AFM/DOD, at least until a couple of years of beta testing.